It+be+形容词(obvious,possible, strange, natural,important...)+that 从句
It+be+过去分词(said,thought,hoped,believed,supposed,reported...)+that 从句
It+be+e+名词短语(apity, a fact, a wonder, a shame, an honour, no wonder)+that从句
It+不及物动词(短语)(seems,occurs,happens,turns out...)+that从句